Some electronic devices have speakerphone capabilities by use of a microphone and loudspeaker. Speakerphones require some form of acoustic separation between the microphone and loudspeaker to prevent echo and other interference with the microphone. Also, speakerphones suffer from nonlinearities in their audio output caused by such things as distortion and non-linear frequency response.
Conventional methods use a prediction of acoustical feedback from a loudspeaker to a speakerphone microphone based on a linear assumption of the loudspeaker's output. Some methods attempt to use echo cancellers, non-linear processing, or noise gates.
Further, some high-fidelity loudspeakers use sense elements and feedback to linearize their outputs.
However, there is a need for an improved system and method for attenuating or eliminating acoustical feedback from a loudspeaker to a microphone. Further, there is a need for an improved system and method for reducing nonlinearities in a speakerphone system. Further still, there is a need to move from a half duplex speakerphone system closer to a full duplex speakerphone system.
The teachings herein extend to those embodiments which are within the scope of the appended claims, regardless of whether they accomplish one or more of the above-mentioned needs.